Field of the Invention
The present disclosure relates to a developer container, a developing device, a process cartridge, and an image forming apparatus. The image forming apparatus here means an apparatus that forms an image on a recording material. The process cartridge means one that has at least an image bearing member. In many cases, the process cartridge is one that is formed by making a charging unit, a developing unit, a cleaning unit, and the image bearing member into a cartridge integrally so as to be detachably attachable to an apparatus main body of an image forming apparatus. Moreover, the developing device means one that has at least a developer bearing member. In many cases, the developing device is one that is formed by integrating the developer bearing member, a developing frame which supports the developer bearing member, and parts related thereto so as to be detachably attachable to an apparatus main body of an image forming apparatus. In addition, the developer container means a container for accommodating developer.
Description of the Related Art
For an image forming apparatus of an electrophotographic system, a cartridge type in which at least a developing unit and a developing device in which developer is accommodated are integrally formed so as to be detachably attachable to the image forming apparatus is widely known. Moreover, a cartridge type is also widely known in which a developing device and an image bearing member unit that has an image bearing member are integrally formed (so-called process cartridge) so as to be detachably attachable to the image forming apparatus (Japanese Patent Laid-Open No. 05-197288 and U.S. Pat. No. 5,030,998).
An image forming apparatus of such a cartridge type is described in Japanese Patent Laid-Open No. 05-197288. Moreover, a configuration of a cartridge, in which a toner supply opening that connects a toner chamber and a toner supply chamber is included, is described in Japanese Patent Laid-Open No. 05-197288.
A toner sealing member is opened in such a manner that one end thereof is attached to a rotating member in the toner chamber and the toner sealing member is rolled up by the rotating member when the rotating member rotates.
By being sealed with the toner sealing member, toner is able to be prevented from leaking out from the cartridge due to an oscillation or an impact caused to the cartridge. Moreover, the toner sealing member of Japanese Patent Laid-Open No. 05-197288 remains in the cartridge after being opened, so that a user does not need to dispose of the toner sealing member. Furthermore, since the user does not need to open the toner sealing member, usability is enhanced.
However, in a case where the automatic rolling-up configuration of the toner sealing member, which is described in Japanese Patent Laid-Open No. 05-197288, is provided in an image forming apparatus, a motor which is a driving source is required to be larger or more expensive in accordance with a maximum rolling-up force. Moreover, it is necessary to secure strength corresponding thereto for parts of a driving system. There is a possibility that such a case may lead to increases in size or cost of an image forming apparatus.
Thus, a technique has been desired to reduce torque at a time of pulling the sealing member.